Conventionally, there is known an image forming apparatus that includes a drum cartridge and a drawer unit. The drum cartridge includes a photosensitive drum. The drawer unit is configured such that the drum cartridge is mounted thereon. The drawer unit includes an exposure head for exposing the photosensitive drum. The exposure head is configured to move between a first position at which the exposure head is adjacent to the photosensitive drum and a second position at which the exposure head is farther away from the photosensitive drum than at the first position.